What is the reason for successful Bluetooth pairing but no sound in Passat?

[Jenkins]

Passat Bluetooth pairing is successful but there is no sound for the following reasons: 1. Check if the phone volume is turned off: Please turn on the phone volume, then check if the car navigation system's volume is turned on, and also verify if the phone is connected to Bluetooth. 2. If the above is not the issue: This is because some car Bluetooth connections, if the car is not on the Bluetooth media audio playback interface, will still play the last media audio source, resulting in no sound when playing music. 3. It is recommended to switch the car to the Bluetooth media audio interface before connecting the phone's Bluetooth: If only the music has no sound, it cannot be ruled out that there is a problem with a specific application version. It is recommended to update all applications to the latest version or try using other applications for comparison.